The present invention relates to testing an optical network, in particular using a test device that is releasably connectable to connector apparatus.
In known optical networks, in particular so-called Passive Optical Networks or PONs, data is broadcast from a head end to a plurality of terminals in a downstream direction. In an upstream direction, that is, towards the head end, data is passively multiplexed. The terminals, which transmit optical data upstream to the head end, are normally configured to transmit data in response to scheduling instructions from the head end. The scheduling instructions control the timing of the data transmissions from the terminals such that data from different terminals is unlikely to overlap.
The terminals are normally installed within customer premises, and will normally be connected to the optical network outside the premises by a standard plug and socket connector.
It can be useful for a network operator to test the network centrally, for example at the head end, by monitoring signals from the terminals. However, if a fault is detected, it can be difficult to determine whether the fault is due to the optical network, or to a terminal. This difficulty can be particularly important if the operator is not responsible for the maintenance of the optical network unit or for other components within the customer premises.
Normally, devices connected to optical networks are electrically powered from the mains supply. Although it is known to derive optical power from an optical source using a photovoltaic device or other solar cell, this is not always convenient.
According to one aspect of the present invention, there is provided a testing system having: connector apparatus for releasably connecting an optical network to a terminal unit, the connector apparatus having an identifier associated therewith, and an identifier circuit for providing an identification signal, which identification signal is indicative of the identifier associated with the connector apparatus; and, a test device that is releasably connectable to the connector apparatus, the test device being operable in use with the connector apparatus to measure at least one characteristic of an optical signal from the optical network, and to transmit a test signal, which test signal includes an indication of the measured characteristic(s) and an indication of the identifier associated with the connector apparatus.
According to another aspect of the present invention, there is provided a method of testing an optical network arranged to broadcast optical signals to a plurality of network connector devices, including the steps of: receiving an optical signal at a connector device; measuring one or more characteristics of the optical signal using a testing device; and, converting optical power in the optical signal into electrical power; and powering the testing device with the converted optical power.